Bending machine for plywood or composition board



1952 E. c. RICHTER 2,582,653

BENDING MACHINE FOR PLYWOOD QR COMPOSITION BOARD Filed June 3, 1949 Q 2 SHEETS-SHEET 1 FIG.

IN V EN TOR.

EMIL 0. RICHTER BENDING MACHINE FOR PLYWOOD OR COMPOSITION BOARD Filed June 5. 1949 E. C. RICHTER Jan. 15, 1952 2 SHEETSSHEET 2 IN VEN TOR.

EM/L G. RICHTER 24 mm w 19mm irralwsys bending machine of Figure 1.

Patented Jan. 15, 1952 4 OFFICE BENDING MACHINE FOR PLYWOOD R COMPOSITION BoAnp Emil o. Richter, St. Louis, Mo. Application June 3, 1949, Serial No. 96,928

2 Claims, (Cl. 144-.-25s

novel and improved bending machine for sheet material which is very simple in construction, very easy to operate, and enabling sheet material I such as plywood or the like to be bent into a great variety of curved-shapes.

A further object of the invention is an improved bending machine for bending sheet material such as plywood, composition board, and the like into curved shapes, said machine applying heat as well as bending pressure simultaneously to the sheet being bent, and being rugged in construction, inexpensive to fabricate, and requiring only a small amount of manual effort on the part of the operator.

Further objects and advantages of theinvenc tion will become apparent from the following description and claims, and from the accompanying drawings, wherein:

Figure l is a side elevational view of a sheet bending machine constructed in accordance with the present invention.

Figure 2 is a top plan view of the machine of Figure 1.

Figure 3 is an end elevational view. of th Figure 4 is an enlarged cross sectional fragmentary detail view taken on line 44 of Fig- 1 I Figure 6 is an enlarged fragmentary cross sectional detail view taken on line 6-43 of Figure 3.

Referring to the drawings, I [designates a rectangular table having a flat top I2 projecting laterally at one side of the table and having a laterally projecting bottom shelf I3. Secured to the end portions of the lateral projection of the table top l2 are upstanding bearing brackets l4, I4 in which is journaled a hollow shaft l5 having pulleys l6, 16 secured thereto adjacent its ends and located outwardly of the respective bearing brackets l4, l4. Rigidly secured to the shaft [5 inwardly adjacent the bearing brackets l4, I I are respective radial arms l1, l1. Rigidly secured on the shaft I5 between the arms l1, I1 is an elongated hollow drum "3 having secured to its ends the respective gears l9, l9. Rigidly secured to the end portions of arms I1, I! is a second hollow shaft extending parallel to shaft I5 to provide bendin and having rotatably mounted thereon a hollow drum 2| coextensive in length with drum l8 and having gears 22, 22 secured to its ends meshing with the gears l9, l9; Rigidly secured to the end portions of shaft 20 are the respective crank handles 23, 23. v

From Figure 3' it will be seen that the laterally projecting portion of table top I2: is substantially aligned with the space between drums l8 and 2|; It will also be apparent that clockwise rotation of shaft 15 will cause arms l1, 11' to swing drum 2| clockwise around drum I8. It will also be seen that gears .22, 22'may berotated counter-clockwise around shaft 20, as viewed in Figure 3, because of their meshing engagement with gears l9, l9, causing drum 2| to be also rotated counter-clockwise. As will; be later explained, this provides an initial gripping action on a sheet of material inserted between the drums for bending; l

Mounted on the "laterally-projecting portion of shelf l3 below the drums is a fluid pressure cylinder 24 having fluid pressure inlet conduits 25 and 26 connected to its end portions. Conduits 25 and 26 are connected to a suitable source of fluid pressure, not shown.: The intermediate portion of the cylinder has an exhaust conduit 21 connected thereto. The pistons of the cylinder 24 are designated respectively at 28, 28. Connected to each piston 28 is a flexible cable 29 extending slidablyand sealingly through an end wall of'the cylinder. Each cable 29 extends over a pulley 30 rotatably mounted on the table leg below one of the pulleys 16 carried on shaft l5. Each cable 29 extends over a pulley I 6 andis secured thereto. When fluid under pressure is introduced into the end portions of cylinder 24 through the conduits .25 and 26, the pistons ;28, 28

are moved inwardly,-providing tension in cables 29, '29, and causing shaft l5 to be rotated clockwise, as viewed in Figure 3; If a sheet of plywood, or other deformable sheet material is placed on the tabletop I 2' and inserted between the drums l8 and. 2 I, said *sheet. may, be; gripped by the drums by first rotating drum 2| counterclockwise and then bent clockwise around drum l8 by introducing fluid under pressure into the end portions of cylinder 24. To facilitate the deformation of the sheet material, each drum contains a heater winding 3| connected through the hollow shaft on which the drum is mounted to a suitable source of voltage. The heat of the drums aids in softening the material for bending.

After the material is bent to the desired arcuate shape it may be released from between the shows the relative positions of the shafts and i drums in final bending position, therbent sheetof material being shown at 32. The bent sheet is finally released by manually rotating drurn'll clockwise.

While a specific embodiment ofabendingmachine for sheet material has been disclosed in the foregoing description, it will be understood-that --of said 'shaft con'tiguous toeachend thereof and secured thereto, asecond drum positioned intermediate said arms. and" mounted th'erebetween for-rotary movement "about'a second horizontal axisspaced from said first horizontal axis, the spacing betweensaid rfirst and second horizontal axes beirig: selected'to provide a space contiguous to said flat top for the extensionjtherethrough of th'e'she'et material 'to' be deformed, means operativelyconnectingisaid second drum" to said first'dr um for 'rotaryniove'ment about said sec- --ond horizontal axis in response to the rotary movement of the assembly of said shaft andsaid first-drum about said'first horizontal axis, and actuating means' 'carried'by said support and-operatively connected to'sai'dl'shaftior effecting the rotary movement of the latter, whereby the :sheet of materialinsertedfbetween said drums will be arcuately bent, said actuating means comprising a fluid pressure cylinder disposed longitudinally "of said'suppor t and secured thereto, a piston'disposed in said cylinder and mounted for sliding movement toward and awayfrom one end there'- fof, a first pulley circumposed aboutsaidshaft and secured thereto,- a second 'pulle'y disposed adjacent to and spacedfrom' saidone end of said cylinder and mounted" on: said framefor rotary -mo'vement about a third: horizontal axis transverse of said first and second named, horizontal axes, and'a flexible cable 'guidingly supported-on s'aidse'cond' pulley and having one end trained aboutisaid "first pulley and secured thereto and having the other end operatively connected to said piston, whereby said second drum will be rotated about said second horizontal axis and said first drum responsive to the admission of fluid under pressure to said cylinder.

2. A machine for bending deformable sheet material comprising a support having a horizontally disposed fiat top,agshaft-spaced above said vflat top and mounted on. said support for rotary movement about a first horizontal axis, a first 'drum circumposed about said first shaft and secured axially thereof, an arm projecting radially ofsaid shaft contiguous to each end thereof and secured thereto, a second drum positioned intermediate: said arms and mounted therebet-ween for rotary movement about a second horizbntal axis spaced from said first horizontal axis, the spacing" between said first and second horizontal axes being selected to provide a space contiguous to said fiat top for the extensionv .therei-nrough of the sheet material to be deformed, means operatively connecting; said second drum to said first drum for rotary movement about said second horizontal axis in response. to the rotary movement of the assembly of said shaft and said first drum about saidvfirst horizontalaxis, actuating means carried by said support and opera- =-tively connected tosaid shaft for eifecting the rotary movement of the latter, whereby the sheet of material inserted between said drums will be arcuately bent, said actuating means comprising a fluid pressure cylinder disposed longitudinally of said support and secured-thereto, a piston disposed in said cylinder and mounted-for sliding movement-toward and away from one end thereof, a first pulley circumposed about said shaft anddsecuredthereto, a secondpulley disposed adjacent to and spaced from said one end of said adapted to be connected to a source of electrical energy.

, EMIL c. RICHTER.

REFERENCES CITED The following references are of record in th file.of this patent: UNITED STATES PATEN S Date Number Name 905,841 7 Cameron Dec. 8, 1908 1,792,595 I Livingston Feb. 17, 1931 

